The Pokédex (Japanese: ポケモン図鑑illustrated Pokémon encyclopedia) was created by Professor Oak as an invaluable tool to Trainers in the Pokémon world. It gives information about all Pokémon in the world that are contained in its database, although it differs in how it acquires and presents information over the different medias. However, they are also only given to a few Trainers at a time, generally to the ones that are felt to have exceptional potential and skill. There are different types of Pokédexes and each Pokédex is special to a specific region.

Pokédex entries are typically only two or three sentences in length, and are bits of information about the Pokémon referred to. In some events it gives background information on the habitat or activities of this Pokémon in the wild; at other times it gives other bits of information on the Pokémon's history or anatomy. The information included is important info on the Pokémon, height, weight (once obtained), cry, other forms, a few sentences about the Pokémon, and a picture of the Pokémon.

Functions

The Pokédex is an handheld electronic encyclopedia device; one which is capable of recording and retaining information of the various Pokémon of the world. In order to accomplish Professor Oak's goal of a complete Pokémon database, the Pokédex is designed to find and record data on each Pokémon the Trainer meets. Pokémon are added to the Pokédex simply by encountering them in battle or (in certain instance) by seeing a picture of the Pokémon. However, detailed entries are not recorded until the player catches the Pokémon, receives it as a prize/gift or acquires it in a trade.

Entries

The main feature of any Pokédex are the entries on each individual Pokémon, which provide a lot of detail that would otherwise be unexplored in the games.

Generation I

In Generation I's Pokédex (model HANDY505), the entries are simple and each individual section can be accessed directly from the listing. The first, and main option—"Data"—includes an image of the Pokémon, its number, name, species, height, weight, and a short blurb. The second option—"Cry"—does not open a new screen; selecting it simply plays the Pokémon's cry. The last option—"Area"—displays the map, along with flashing indicators at each location where the selected Pokémon can be found; in cases where the Pokémon is not available in the wild, is only available once, or can only be found by fishing or in Cerulean Cave, the message "Area Unknown" will be displayed over the center of the map instead. Pokémon Yellow allows players to print entries using the Game Boy Printer.

Generation II

Generation II retains the same elements as its predecessor, while adding the Pokémon's footprint to the information and, like Yellow, allows players to print entries. Unlike Generation I, selecting a Pokémon displays the entry in a new screen from which the other sections can be selected. This became the norm for subsequent generations. International versions also have a "Page" button for long Pokédex entries (in Generation I player simply had to press A button instead); Japanese versions did not have multi-page Pokédex entries.

In these games, entries that would normally display "Area Unknown" on the map simply display an unmarked map.

Generation III

Generation III's Pokédex did not add anything to the main entry; however, Cry was given its own page, which displays the soundwave as it played. In addition, the Area section was changed to highlight locations instead of just marking them and can now display the locations of Pokémon obtainable by fishing. A Size section was added, which displays silhouettes of the Pokémon and the player character side by side. In Pokémon Ruby and Sapphire only, there is a Page button to switch between pages of multi-page Pokédex entries.

FireRed and LeafGreen's Pokédex (model HANDY909) displays entries in a much different format from Ruby, Sapphire and Emerald. It was the first Pokédex to actually display a Pokémon's type in its entry, as well as its menu sprite. However, the Cry visuals were removed. Entries for Kanto Pokémon were taken from Red/Green for FireRed and Red/Blue for LeafGreen. Johto Pokémon entries were taken from Silver for FireRed and Gold for LeafGreen. Additionally, in the international versions, it is the first Pokédex to show long Pokédex entries in full, instead of splitting them into two pages. This was carried over to later games, including Emerald.

Generation IV

Generation IV's Pokédex (model HANDY910is) added numerous features, but of FireRed and LeafGreen's changes, it kept only type. Area now changes its highlight color depending on whether a Pokémon is found normally or exclusively using Honey, and the player can view the differences between morning, day and night, with the default being the current time. Cry's display returned, with a bar display in addition to the wave display, and the ability to modify the cry via Chorus/Pan, Reverb/Filter and Loop. Weight was added to the Size section, which puts the Pokémon and the player character on either side of a balance scale. A new Forms section allows players to see gender and form differences within species, but only for forms they have already seen. For a small list of Pokémon, if the player obtains a Pokémon from another country, they can change the language of that Pokémon's entry after meeting Meister. In Platinum, this function was expanded to all Pokémon, although it still requires Meister to update the Pokédex.

HeartGold and SoulSilver changed the formatting again, now displaying the list on the lower screen and the actual entry on the top screen. Cry's page was again removed. By selecting "view details", players can view Area, Size and Forms. Area no longer defaults to the current time or differentiated for Honey due to it no longer being a mechanic, Size now utilized both screens to display both Height and Weight at the same time, and Forms added a Compare option to see different forms side by side instead of having to scroll between them. Entries for Johto and Kanto Pokémon were taken from Gold for HeartGold and Silver for SoulSilver. Players can collect foreign Pokédex entries without the need to update their Pokédex. Also, while artwork shows a pink Pokédex for females, the in-game interface does not reflect this.

Generation V

The Generation V Pokédex is similar to the Pokédex from Pokémon Diamond, Pearl, and Platinum. It is displayed as a list on the right side of the lower screen with the selected Pokémon's sprite occuping the left side. Most of its functions are also similar to Generation IV's. Instead of showing the time of day that a Pokémon can be caught, as in Generation IV, the Pokédex shows the seasons in which it can be found. Areas in which the Pokémon can be found flash red, and touching an area will show the methods by which it can be caught (walking in tall grass, surfing, or fishing). The height and weight comparison feature has been removed, but a section showing form differences and a search feature are added by Cedric Juniper when the player visits Mistralton City. The form difference section will now show Shiny Pokémon as well as form differences. The last sprite selected will become the one displayed in the main entry. The ability to collect foreign Pokédex entries now only applies to the first 493 Pokémon, but the player can now also collect Korean Pokédex entries. The cry page has been added again as well.

In Black 2 and White 2, after defeating Cheren for the first time, Bianca will upgrade the player's Pokédex to the Habitat Mode, showing which Pokémon the player has already seen in the selected location, either normally, by finding in the water or via fishing rod (the latter two available later). If all Pokémon available in that place that are available via one of these three ways are seen (such as Purrloin and Patrat for tall grass on Route 19), the reference to the location in such way is marked with a Poké Ball-like stamp; after catching all Pokémon that are found via one of these three ways in current place, it gets marked with a colored Poké Ball-like stamp.

In Ruby and Sapphire, the search function was expanded to allow searches by name and color. Players were also given the option to order Pokémon by Heaviest, Lightest, Tallest, or Smallest. Two modes were available, Hoenn and National. National mode was unlocked via a trade with Kanto or Orre, or in Emerald, defeating the Elite Four.

However, in FireRed and LeafGreen, the search function was dropped altogether, instead choosing to expand the sort functions by adding lists of Pokémon by type and habitat. Heaviest and Tallest orders were also removed. National Mode was unlocked by having obtained 60 Pokémon in the Pokédex, beating the Elite Four and completing the Sevii Island's sidequest.

Generation IV brought the Search function back, as well as Heaviest and Tallest orders. Habitat was dropped. Searches could now be conducted by Form, but not by Color. The two Pokédex modes were Sinnoh and National. National mode was unlocked by seeing every Pokémon in the Sinnoh Dex.

Completion

Diploma awarded in Red/Blue

Completing the Pokédex is a common goal of Trainers and carries with it much esteem due to its difficulty, which has gradually escalated due to the fact that at least 100 new Pokémon are introduced with each new generation. However, this is circumvented to a degree with new features added to the games, such as the introduction of Wi-Fi and the Global Trade Station in Generation IV, or a more convenient trading system (PC box to PC box) in Generation V. The exclusion of event Pokémon as a requirement for completing the Pokédex also makes it possible for people with no access to event distributions to complete the Pokédex.

The in-game rewards are usually a congratulations from the director's avatar and a diploma, usually one for completing the regional Pokédex and one for the National Pokédex. In Emerald, the player could choose from one of the Johto starter Pokémon for completing the Hoenn Dex. The completion of the Pokédex also usually allows the player to upgrade his/her Trainer Card.

In Generations I to III, the completion of the regional Pokédex is tracked by how many Pokémon the player has caught. However, in Generation IV, the regional Pokédex is tracked simply by how many Pokémon the player has seen. In Generation V, the requirement is again to catch all Pokémon in the Unova region. Completion of the National Pokédex is strictly based on the number of Pokémon caught.

In the anime

When a young "Sammy" Oak was accidentally warped to a future of his own time, Ash explained to him how the Pokédex works, unknowingly giving him an idea. This is an example of a Bootstrap paradox. This means the idea for the Pokédex came out of nowhere.

In Pokemon - I Choose You!, Ash receives his first Pokédex, apparently nicknamed "Dexter". Throughout the series, Ash uses it to either identify Pokémon he isn't familiar with, check a Pokémon's moves, or identify Pokémon on request. Occasionally, though, Ash will scan Pokémon he has already seen, likely to either refresh his memory or out of curiousity.

In The Evolution Solution it was mentioned that the Pokédex entries were written by Professor Westwood V of the Seafoam Islands. Unlike the games, entries in the anime are pre-programmed into the database and do not require catching to give full information. In this way, they act more as a true encyclopedia than a data recording device. However, it should be noted that information relayed to the user may vary from time to time. This may happen even if the Pokédex remains unchanged in any way.

To look up information on a particular species, Trainers may simply point the Pokédex at an individual or manually enter it in. The Pokédex will then display a picture and read the entry out loud. In the Diamond and Pearl series, it was revealed that it can identify the Pokémon's level and learned moves, even for wild Pokémon. Apparently, a picture or video recording of sufficient quality can also be scanned for information.

Like in the games, the Pokédex has gone through various designs. This includes its shape and way of opening, display, as well as the aforementioned voice. The Unova Pokédex redesign in the anime is significant, as it shows all the viewing angles from the Pokémon, with the exception of the back.

In the manga

In the Pokémon Adventures manga

In Pokémon Adventures, only a select group of people have Pokédexes and they are highly respected as a result. The Pokédexes come in groups of three per region, and are generally given out along with a starter Pokémon from the region's Professor. Each Pokédex has a holder registration system, meaning when it is assigned, the holder must register his or her name and fingerprints, which means each of the Pokédexes is only allowed to have one rightful owner. However, it is possible to transfer data from one Pokédex to an upgraded version, leaving the Pokédex that had its data transferred with no rightful owner, and thus, the Pokédex would be able to be reassigned to a new owner. It is shown that when the three Pokédexes from the same region are put together, a Pokédex will make a beeping sound as a signal to indicate that another Pokédex is nearby. This only works when held by their rightful owner, as seen in Gimme Shellder. This signal seems to apply for all models of the Pokédex, and the Sinnoh Pokédex holder trio refers to it as the "morning sound" (Japanese: 朝の音).

Much as in the anime, the Pokédex in Pokémon Adventures displays the known moves of an individual Pokémon, as well as its current health, its cry, its current moves, and can even track them. Unlike in the anime, the Pokédex entries are usually taken directly from the games and as such contains readable text rather than having the information spoken out loud. The Pikachu interaction feature from Pokémon Yellow was added to Red's Pokédex, allowing him to see its mood (though he never is seen making much use of it, as Yellow was in possession of his Pokédex for most of the Yellow chapter, and could tell Pika's mood on her own anyway). The Pokédex's function takes over much of the control the games give to the player, being able to prevent a Pokémon's evolution, whereas Trainers without a Pokédex have no choice in the matter. As seen in Wanted: Pikachu!, the Pokédex can discover where a Pokémon was first met by its Trainer, much as the feature added in Pokémon Crystal allows one to view a Pokémon's origin.

In the FireRed & LeafGreen chapter, Professor Oak asks Red, Blue, and Green to return their Pokédexes to him, so that he could upgrade them to National Dex. Though in the process, they get stolen by Orm and used by Carr to create a "black Pokédex" (Japanese: 黒い図鑑). Later in the story, the new Pokédexes are received by the trio, and Red's old one is given to Yellow. In the HeartGold & SoulSilver chapter, the Johto Pokédex holders get new Pokédexes as well, though it is unknown what happened to their original Pokédexes.

In The Electric Tale of Pikachu manga

A Pokédex in the Electric Tale of Pikachu

In the manga series The Electric Tale of Pikachu, Pokémon Trainers receive their Pokédexes when their application to become a Pokémon Trainer is accepted. A Pokédex contains information on a Pokémon's moves and abilities, as well as general information (such as how some Pokémon, like Pikachu, dislike Poké Balls) and the ability to tell if a Pokémon has critically low HP. In addition, all Pokédexes contain a copy of the Trainer's license.

Updated versions of the Pokédex are released from time to time: in Clefairy Tale, Professor Oak gives Ash a beta version of the latest model of the Pokédex.

In the TCG

Pokédex HANDY910is

This listing is of cards mentioning or featuring the Pokédex in the Pokémon Trading Card Game. The Hoenn region's model did not receive a TCG card, and the Generation I and Generation II Pokédexes, which featured model numbers on the Japanese cards (HANDY505 and HANDY808 respectively), did not show these model numbers on the English card. The Generation V Pokédex has no model number even in the Japanese card; it also has the same effect and English name as the Generation I Pokédex. Every card has allowed the player to look at a certain number of cards from the top of their deck and then either arrange them as they like, or in the case of Pokédex HANDY910is, choose one to put in their hand.

Related cardsCards listed with a blue background are only legal to use in the current Expanded format.Cards listed with a silver background are legal to use in both the current Standard and Expanded formats.

Most of the Pokédexes appear similar to one of Nintendo's handhelds. The Johto Pokédex resembles a Game Boy Color, the Hoenn Pokédex appears similar to the Game Boy Advance, the Generation III Kanto Pokédex resembles a Game Boy Advance SP, the Sinnoh Pokédex resembles Nintendo DS Lite, and the Generation IV Johto Pokédex is in similar appearance to a Nintendo DSi. However, the Generation V Unova Pokédex does not look like the next handheld, the Nintendo 3DS, but rather an iPod.

The Pokédex is evidently encased in material that is invulnerable to almost anything within reason. It has been soaked in water and (in the anime) electrocuted and exposed to high-temperature flames, all with no ill effect. It is also voice-sensitive. There are some limitations to its ability; certain circumstances can prevent the Pokédex from accurately identifying its target:

A Pokédex which has not received a National Mode upgrade will not display any information on Pokémon not usually found in its home region, even if those Pokémon have been caught.

Similarly, Gary's Pokédex failed to identify Mewtwo at the Viridian Gym, displaying only static interference. This may be attributed to the mechanical battle armor Mewtwo was wearing at the time.

All six of Ash's Pokédexes have been red, as were the Pokédexes in the games prior to HeartGold and SoulSilver, while other characters have had other colors. May had a yellow one in Kanto, Paul has a dark blue Pokédex, Dawn has a pink Pokédex, Rhyanna has an ice blue Pokédex, Narissa has an orange Pokédex and Mamie has a lavender Pokédex.

The only Pokédex Ash has never owned is the Pokédex introduced in HeartGold and SoulSilver.

The Kanto regional Pokédex and the Sinnoh regional Pokédex (Diamond and Pearl) have 151 members, the smallest of all regional Pokédexes. The largest regional Pokédex is the New Unova regional Pokédex, with 301 members.

The Pokédex models of GenerationsI and II rounded the weights of all Pokémon to full pounds except for Gastly and Haunter, despite the Japanese games' use of tenths of kilograms since the start. From Generation III onward, all weights have been given to the nearest tenth of a pound.

The Pokédex lost several buttons with every new model, due to various upgrades: Kanto's first model has twenty-two buttons, Johto's original model has five, Kanto's second model, Hoenn's, and Sinnoh's only have three, and Johto's second model apparently has none whatsoever, solely using the touch-screen interface.